Let me start by saying I am more or less on your side of the issue. I don't own the gun. But I don't care if my neighbor owns one for hunting, or as a hobby, or to feel safer. With that said let me give you some advice.
There is way too much passion. It is clear you are very anti gun control. That means you have a very obvious agenda, and I should be very cautious when reading your post.
Now honestly most of what you are saying might be completely true. But the way you are talking won't convince anyone on the opposite side or in the middle of the issue. You are just pandering to your side and politicizing the issue yourself.
Let me give you an example on how to improve.
On the off chance that you need a reminder that money cannot buy you brains, I give you the ultra-rich, ultra-liberal, ultra-anti-gun, ultra-moron, Michael Moore who, in a statement he posted on Facebook, blames, among other things, congress for not passing stricter gun laws that “90% of Americans want”. Hey genius, this incident happened in CA, where all of those stricter gun laws you claim that 90% of us want already exist. This once again proves what we (those of us who can actually use our brains) have been saying for decades: More gun laws cannot possibly prevent crimes like this.
Note the things I highlighted. Avoid statements like those. They are exactly the type of venom that for some reason both sides use, even though they just make the other side look at you with animosity, and make people who haven't formed opinions tend the ignore you.
Had you written something like this, it would have been far more effective at convincing people who don't share your opinion.
Michael Moore who, in a statement he posted on Facebook, blames, among other things, congress for not passing stricter gun laws that “90% of Americans want”. But the sad truth is that this incidident is an example of even strict gun control laws not working. Despite all the precautions that the state of California takes towards gun ownership. This man still managed to get a gun. Where there is a will, there is a way. If someone wants to get a gun, he will find a way to get one. More gun laws cannot possibly prevent crimes like this.